No result found
Submarine canyons have been shown to positively influence pelagic and benthic biodiversity and ecosystem function. In the eastern Bering Sea, several immense canyons lie under the highly productive "green belt" along the continental slope. Two of these, Pribilof and Zhemchug canyons, are the focus of current conservation interest. We used a maximum entropy modeling approach to evaluate the importance of these two canyons, as well as canyons in general, as habitat for gorgonian (alcyonacean) corals, pennatulacean corals, and sponges, in an area comprising most of the eastern Bering Sea slope and outer shelf. These invertebrates create physical structure that is a preferred habitat for many mobile species, including commercially important fish and invertebrates. We show that Pribilof canyon is a hotspot of structure-forming invertebrate habitat, containing over 50% of estimated high-quality gorgonian habitat and 45% of sponge habitat, despite making up only 1.7% of the total study area. The amount of quality habitat for gorgonians and sponges varied in other canyons, but canyons overall contained more high-quality habitat for structure-forming invertebrates compared to other slope areas. Bottom trawling effort was not well correlated with habitat quality for structure-forming invertebrates, and bottom-contact fishing effort in general, including longlining and trawling, was not particularly concentrated in the canyons examined. These results suggest that if conserving gorgonian coral habitat is a management goal, canyons, particularly Pribilof Canyon, may be a prime location to do this without excessive impact on fisheries.
The Pew Charitable Trusts;
In the Bering Sea, science-based management of major fisheries is designed to control fishing at levels that maintain stable populations of valuable fish. But a single-species approach to managing fisheries does not always consider the interconnections among marine organisms. Many scientists argue that although good single-species management is necessary, fishery managers also need to look at the bigger picture. Ecosystem-based fisheries management is a way to sustain the health of our oceans by accounting for the interconnections among marine life, an ever-changing environment, and human activities including commercial, recreational, and subsistence fishing. Tools and approaches to aid in ecosystem-based fisheries management are available to reduce bycatch; conserve important habitat; protect marine food webs; monitor ecosystem health; and evaluate the ecological, social, and economic trade-offs of different management actions. In the Bering Sea, many of these tools are being applied. Yet more will be needed to steward this ecosystem in the years ahead. As our knowledge of the Bering Sea ecosystem grows, as demand for seafood increases, and as impacts of climate change are felt, fishery managers must put a long-term plan in place to address the challenges the future will bring.
The Pew Charitable Trusts;
This brief examines the risks posed by increasing vessel traffic and outlines a series of mitigation measures that authorities can implement to protect all those who depend on the Bering Strait—wildlife and indigenous communities, as well as ships and their crews.
Journal of Local and Global Health Science;
This study was conducted in order to determine if the source of contaminants at formerly used defense sites (FUDS) in Alaska were deposited as a result of military occupancy or from long-distance transport. This determination largely influences whether remediation will occur, and, if so, to what extent. For this reason, plant samples (rinsed and unrinsed) and sediment cores were collected at military and remote sites on St. Lawrence Island (SLI) and Norton Sound, Alaska during the summers of 2002, 2006, and 2007 and analyzed for persistent organic pollutants. On St. Lawrence Island sediment core samples were collected at the Northeast Cape FUDS, also a traditional fishing/hunting camp, and were sectioned and analyzed for concentrations of Polychlorinated biphenyl (PCB) congeners, Mirex, Dichlorodiphenyldichloroethylene (DDE), Hexachlorobenzene (HCB), Mercury and Cesium-137 (137Cs). Differences in the total concentrations and distributions of PCB congeners, Mirex, DDE and Mercury in sediment cores and in plants collected from the two SLI and three Norton Sound mainland formerly used defense sites indicate the majority of the contaminants found can be temporally related to releases during military occupancy and subsequent redistribution of contaminants. Contaminants in plant samples at the SLI sites are elevated relative to the two remote sites located on St. Lawrence Island and the three mainland Norton Sound FUDS at Elim, Unalakleet, and Wales. The concentrations, lateral and vertical distribution of the total PCBs, and congener-specific differences in sediments and plants readily differentiate locally derived from globally transported contaminants. The relative contaminant concentrations in sediment cores and between rinsed and unrinsed plants collected from the NEC FUDS indicate contaminants were remobilized and redistributed during recent site remediation activities.